单分散镍碳复合纳米球和碳微球的制备

Preparation of monodisperse Ni/C nanospheres and carbon microspheres

以脱油沥青(deoiled asphalt)为碳源,采用化学气相沉积法(CVD)制备碳微球,其裂解后的残渣经真空热处理制得单分散镍碳复合纳米球。用场发射扫描电镜(FESEM)、高分辨透射电镜(HRTEM)和X射线衍射仪(XRD)对产物进行表征。结果表明,碳微球高纯,属无定型碳结构,大小分布在1～2μm范围内;镍碳复合纳米球为准球形核壳结构,核为镍,壳为碳,尺寸在10～30nm范围,晶化程度较高,结构较完善。

Carbon microspheres were prepared from deoiled asphalt （DOA） by chemical vapor deposition （CVD）. Furthermore,monodisperse Ni/C nanospheres were obtained by vacuum heat-treatment using the residue coke from previous experiment as carbon source and nickel powder as catalyst. The morphologies and structures of the products were characterized by field emission scanning electron microscopy （FESEM）, high resolution trans- mission electron microscopy （HRTEM） and X-ray diffraction （XRD）. Results showed that high purity and amorphous structure carbon microspheres with diameters ranging from 1-2μm was achieved,that Ni/C nanospheres with size 10-30nm exhibited obvious core-shell structures with nickel as cores and carbon as shells. Carbon shells surrounding the aetal particles may offer excellent protection to the encapsulated metal nanomaterials .